Abstract: A marine drive cathodic protection control circuit and method controls ohmic current from a power source to an anode according to electrical reference potential sensed by a reference electrode. The ohmic current is interrupted for an interruption interval, and reference potential is sensed during the interruption interval. The ohmic current is controlled according to reference potential sensed during the interruption interval.

Abstract: A detection system senses the location of a preselected color within one or more monitored zones of a machine tool. If the operator of a machine tool wears a red glove, the system detects the location of the color red and defines various monitored zones through the use of synchronization signals and a time circuit. The system can take action based on the location of the particular monitored zones in which the red glove is sensed. These actions can include the sounding of a horn, the lighting of a light, or the deactivation of the machine tool.

Abstract: A method for manufacturing a submerged surface, such as the hull of a marine vessel or a submerged grate or conduit, uses particles that are electrically conductive and disposes those particles on the exposed surface. The particles are held in, place by an electrically conductive composite material, such as a conductive gel coat, and a charge distribution layer is used to spread the current through all parts of the conductive outer surface.

Abstract: A method for operating a system which inhibits the growth of marine organisms on a submerged surface causes a current to flow to one of two submerged surfaces over a time period that is selected as a function of the magnitude of the current and the area of the surface. In other words, the time period is determined as a function of the current density applied to the surface. In a particularly preferred embodiment the current density is maintained at approximately 35 milliamps per square foot and the time period is approximately four minutes. At the end of the time period, the current is reversed and a second submerged surface is polarized in a similar manner.

Abstract: A method is provided by which a position of a marine vessel can be determined relative to a stationary object, such as a dock. Two position sensors are attached to a marine vessel and a microprocessor, onboard the marine vessel, computes various distances and angular relationships between the position sensors on the marine vessel and stationary transponders attached to the fixed device, such as a dock. The various dimensions and angular relationships allow a complete determination regarding the location and attitude of a marine vessel relative to the dock. This information can then be used by a maneuvering program to cause the marine vessel to be berthed at a position proximate the dock.

Abstract: Two sensor units are mounted on opposite sides of a transom of a boat and directed to a common location behind the boat. The field of view of the two sensors overlaps behind the marine propulsion unit of the boat to detect the presence of a heat emitting object, such as a mammal. Housing structures contain infrared sensing elements, lenses, and light shields. Signals from four infrared sensing elements are received by a controller which reacts, with an alarm signal, when at least two of the four sensors detect a heat emitting object within their individual fields of view. False triggering can be reduced by not providing an alarm signal if only the two most inboard sensors detect the heat emitting object.

Abstract: Two sensor units are mounted on opposite sides of a transom of a boat and directed to a common location behind the boat. The field of view of the two sensors overlaps behind the marine propulsion unit of the boat to detect the presence of a heat emitting object, such as a mammal. Housing structures contain infrared sensing elements, lenses, and light shields. Signals from four infrared sensing elements are received by a controller which reacts, with an alarm signal, when at least two of the four sensors detect a heat emitting object within their individual fields of view. False triggering can be reduced by not providing an alarm signal if only the two most inboard sensors detect the heat emitting object.

Abstract: Two sensor units are mounted on opposite sides of a transom of a boat and directed to a common location behind the boat. The field of view of the two sensors overlaps behind the marine propulsion unit of the boat to detect the presence of a heat emitting object, such as a mammal. Housing structures contain infrared sensing elements, lenses, and light shields. Signals from four infrared sensing elements are received by a controller which reacts, with an alarm signal, when at least two of the four sensors detect a heat emitting object within their individual fields of view. False triggering can be reduced by not providing an alarm signal if only the two most inboard sensors detect the heat emitting object.

Abstract: Two sensor units are mounted on opposite sides of a transom of a boat and directed to a common location behind the boat. The field of view of the two sensors overlaps behind the marine propulsion unit of the boat to detect the presence of a heat emitting object, such as a mammal. Housing structures contain infrared sensing elements, lenses, and light shields. Signals from four infrared sensing elements are received by a controller which reacts, with an alarm signal, when at least two of the four sensors detect a heat emitting object within their individual fields of view. False triggering can be reduced by not providing an alarm signal if only the two most inboard sensors detect the heat emitting object.

Abstract: A ceramic conductor is supported by an electrically insulative support member for attachment directly to a marine propulsion drive and for use as either an anode or electrode in a corrosion prevention system. The ceramic conductor is received within a depression formed in a surface of the electrically insulative support member and the exposed surface of the ceramic conductor can be offset from or coplanar with an exposed surface of the electrically insulative support member. The ceramic conductor can comprise oxides of iridium, tantalum and titanium that are formed as a coating on a titanium substrate.

Abstract: A monitoring system detects the presence or absence of a marine vessel operator within a defined zone near the helm of a marine vessel. The detection is accomplished through the use of a provision of an e-field and the detection of e-field strength by a receiving antenna system. When the operator is in the proper helm position, the e-field strength is diminished by the presence of a portion of the operator's body within the e-field zone.

Abstract: A marine fouling inhibiting system comprises first and second conductors which are made of a polymer matrix, such as vinyl ester, and a suspended conductor, such as graphite powder or particles. This type of conductive material is formed to provide two sections of a boat hull so that a source of electrical current can be used to reversibly cause an electric current to flow to and from the conductive coatings. The conductive coatings are electrically insulated from each other in order to force the formation of an electrical circuit which includes the two conductive coatings, the source of electrical current, and the water in which the boat hull is disposed. This results in the creation of chlorine bubbles on the conductive surfaces. Chlorine bubbles on the boat hull surfaces discourage the formation of marine growth, such as barnacles.

Abstract: An anode for a cathodic protection system comprises a base portion or support structure which is shaped to receive a conductive element, or insert, within a cavity of the support structure. The conductive element is made of a polymer material, such as vinyl ester, with a conductive filler, such as graphite powder. The base is attachable to a marine vessel or other submersible component that is being protected by a cathodic protection system. The anode allows the use of a relatively inexpensive resin material with a graphite filler in place of a much more expensive platinum coated titanium element.

Abstract: The calibration procedure allows an upward maximum limit of tilt to be automatically determined and stored as an operator rotates a marine propulsion device relative to a marine vessel with a particular indication present. That indication can be a grounded circuit point which informs a microprocessor that at calibration procedure is occurring in relation to an upward trim limit. When the ground wire is removed or disconnected from the circuit point, the microprocessor knows that the calibration process is complete. During the rotation of the outboard motor or marine propulsion device in an upward direction, both the angular position of the outboard motor and the direction of change of a signal from a trim sensor are stored.

Abstract: An electrically conductive coating is provided on a housing structure of a marine propulsion system. By impressing a current on the electrically conductive coating, which can be a polymer material, the housing structure is used as an anode in a cathodic protection system. In addition, the use of the electrically conductive coating on the housing structure as an anode inhibits the growth of marine fouling on the outer surface of the housing structure by forming chlorine gas in a saltwater environment and by forming an acidic water layer near the surface in a non-saltwater environment.

Abstract: A detection system and method for a marine vessel uses an infrared sensor to detect the presence of a human being or mammal in a target area near the propulsor. A visible light detector is used to determine whether or not a signal received from the infrared sensor is caused by reflected sunlight and not the actual presence of a human being or mammal. By detecting visible light, false triggering of the system in response to infrared radiation received from sunlight can be significantly reduced. Embodiments of the system can monitor gear position and engine speed in combination with signals received from the infrared sensor and visible light sensors to determine an appropriate action to take in response to the presence of infrared radiation above a preselected threshold.

Abstract: A method for inhibiting galvanic corrosion of marine propulsion components impresses an electronic current into the protected component and causes the protected component to act as a cathode in a galvanic circuit which comprises a conductor, such as a ground wire connected between the protected component and an electrical conductor which is external to the marine vessel on which the protective component is attached. The electrical conductor can be a ground wire of an electrical power cable connected between the marine vessel and the shore ground. The sea bed is caused to act as an anode in the galvanic circuit, with varying voltage potentials existing within the water between the sea bed and the protected component. The system can be a closed loop control circuit using a voltage sensed by an electrode, or an open loop circuit that provides current pulses based on empirical data.

Abstract: A multilayered submersible structure has an outer coating that is disposed in contact with water in which the structure is submerged, a current distribution layer or charge distribution layer, an electrical conductor connectable in electrical communication to a source of electrical power, and a support structure. By selectively energizing the current distribution layer, or charge distribution layer, chemical and ionic changes can be caused in the water immediately adjacent the outer coating or layer to inhibit the growth of marine organisms on the outer surface of the submersible structure.

Abstract: A system is provided which automatically calibrates a marine fouling prevention system. It responds to movements between fresh and saltwater bodies of water, detects damage to the hull or other submerged surface, and responds to the use of the fouling prevention system with different sizes of marine vessels.

Abstract: A monitor for use in conjunction with a galvanic protection system for a marine vessel provides automatic and continuous monitoring of a voltage at a reference electrode of the galvanic protection system and displays the results continuously by energizing one or more of a plurality of annunciators, such as light emitting diodes. The light emitting diodes are energized in groups of one or two in order to double the effective resolution of a group of ten annunciators. The selected annunciators are energized intermittently in order to conserve electrical power while continuously and automatically running. The frequency of activation of the selected annunciators is changed whenever the voltage potential being monitored falls within a minimum range or a maximum range in order to alert the operator of a potentially catastrophe result. A lower frequency is used when the monitor voltage is not within these minimum and maximum ranges.